Posting this at my wife's request: She has a very-highly-modified 1986 Buick Grand National. It's parked for the winter, but a driver in warm weather. The engine is a fire-breathing Stage II stroker (272ci) V6 that put over 700HP down at the wheels (easily 800+ at the crank). As you might expect of a turbo engine making better than 3hp/ci, it's pretty brutal on oil. We have done what we can (big oil cooler, oversized Chevy MDT oil filter, big oil pan), but even with all this, it still sees oil temps over 300 degrees and has topped 350. (Pre-cooler, it pinned the gauge at over 400!)
I think the current fill is 5W-50, I think Castrol Syntec, that being the only 5W-50 we could find on anything like a regular basis. What's in the car was the last of what we had, so we will need to switch. Any suggestions? Mobil or Rotella 5W-40 would seem like it might work...?
High-temp oil for turbo car
- Thread starter Jarlaxle
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JHZR2
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This is where an ester oil comes into the picture, I'd grab the redline with highest HTHS.
With those mods to support the oil longevity, and temperatures, IMO, the car is not designed to make such power. I doubt you would notice a difference dialing it back a few hundred for most uses.
There is a Mobil 1 5w-50 that you should be able to get through Mercedes, Lexus, and possibly Porsche dealerships. I'd use that over Syntec 5w-50 or any xw-40 on the shelf, honestly.
There is also Castrol TWS 10w-60, which definitely is available in large quantities through any BMW dealership.
Both of those oils are race-bred and designed to take very, very high temps -- more than any oil you'll find on the shelf.
EDIT: I second the suggestion to consider Red Line, but it usually isn't available in stores. If you're going to consider online or phone ordering, also look at RLI and Motul 300V.
EDIT 2: OP, have you considered a liquid heat exchanger for the oil?
for anything that high output you have to go Dominator.
A real race oil that actually wins races.
FWIW I run it in a very expensive blown Chevy BB stroker in a go-fast boat. Excellent results per oil analysis.
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Originally Posted By: Jarlaxle
very-highly-modified 1986 Buick Grand National.
Spare no expense on that beast! Redline,Amsoil,or Royal Purple 50 weight.If you dont have a cat run mobil1 0w50 racing oil, it will take anything that engine can throw at it
Those are oil temps that engines are not supposed to operate at so I'd use Redline xW-50 because of the high thermal stability, low volatility, and high HTHS viscosity. I would not use any oil that is mostly Group III.
Originally Posted By: SteveSRT8
for anything that high output you have to go Dominator.
A real race oil that actually wins races.
FWIW I run it in a very expensive blown Chevy BB stroker in a go-fast boat. Excellent results per oil analysis.
Originally Posted By: d00df00d
EDIT 2: OP, have you considered a liquid heat exchanger for the oil?
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Just curious if you run an oil temp & pressure gauge to verify the oil type?
I third or fourth the RedLine, Amsoil suggestion. These are two companies with a lot of races under their belts, with highly modified engines under extreme environmental pressure.
C'mon, Z rod is for older classics with flat tappets and little use. More intended for garage queens than daily drivers.
http://www.amsoil.com/storefront/zrt.aspx
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Originally Posted By: d00df00d
Isn't Shell Rotella T6 a Group III+ product? I think this case is one of the few in which it is appropriate to seek a product that is made with group IV/V base stocks because the conditions are so extreme.
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